Randy, Please check my math

[Miami Reef]

To make a 35ppt refractometer solution.

From Randy‘s article:

dissolving 3.65 grams of sodium chloride in 96.35 grams (mL) of purified freshwater

https://reefkeeping.com/issues/2004-06/rhf/index.php


I measured 1L of water and added 37.9g of Iodized salt TO the 1L of water (making a solution that is slightly greater than 1 L).

Did I do this correctly? I want to be as perfect as possible.

 

[Randy Holmes-Farley Verified Community Expert]

Well, let’s check. 1L of water at 25 deg C has a density of 0.99705 and thus weighs 997.05 g.

thus, you made a solution that is 37.9 g /(997.05 + 37.9) x 100% = 3.66%. You wanted 3.65% so yes, it is very close. How close depends a bit on the temp, but close enough to 35 ppt in any case.

 

[gbroadbridge]

To make a 35ppt refractometer solution.

From Randy‘s article:

https://reefkeeping.com/issues/2004-06/rhf/index.php


I measured 1L of water and added 37.9g of Iodized salt TO the 1L of water (making a solution that is slightly greater than 1 L).

Did I do this correctly? I want to be as perfect as possible.

Tastes right to me. But I'll wait for Randy because chemistry is wierd sometimes.

 

[Miami Reef]

Well, let’s check. 1L of water at 25 deg C has a density of 0.99705 and thus weighs 997.05 g.

thus, you made a solution that is 37.9 g /(997.05 + 37.9) x 100% = 3.66%. You wanted 3.65% so yes, it is very close. How close depends a bit on the temp, but close enough to 35 ppt in any case.

Thank you, Randy.

 

[Garf]

Thank you, Randy.

Congratulations, you now have 30 years worth of calibration solution, lol.

 

[Miami Reef]

Congratulations, you now have 30 years worth of calibration solution, lol.

I wanted to use my 1L volumetric flask because it is one of the most accurate devices to measure volume. :D